The present invention relates to a Kirschner wire for use in endoscopic surgery, as well as methods and apparatus for installing and removing the Kirschner wire. In particular, the present invention relates to a Kirschner wire having a holding device at a proximal end for ease of insertion and removal of the Kirschner wire. The Kirschner wire is sufficiently short so as not to protrude from the working channel of the endoscope. The insertion instrument has a receptacle which is adapted to engage with the holding device of the Kirschner wire. A targeting ring on the insertion instrument enables placement of the Kirschner wire under x-ray supervision. A removal device has a wire body with a receptacle located at a distal end thereof for engagement with the holding device of the Kirschner wire. The Kirschner wire may be adapted for use in marking a point of entry for a cannulated bone screw or as a point of orientation for an endoscopic procedure.
During endoscopic surgical procedures, such as spinal surgeries and the like, there is normally a single working channel provided by the endoscope. For surgical techniques that require the use of a Kirschner wire, the Kirschner wire may protrude from the working channel once in place. Alternatively, a shorter Kirschner wire may be used that does not protrude from the working channel. However, removal of such short Kirschner wires are difficult.
It would be advantageous to provide a sufficiently short Kirschner wire that does not protrude from the working channel of an endoscope, but that is easily removed. It would also be advantageous to provide a holding device on the proximal end of the Kirschner wire to aid in removal of the Kirschner wire. It would be further advantageous to provide an insertion instrument for placing such a short Kirschner wire endoscopically and a removal device for removing said short Kirschner wire endoscopically. It would be still further advantageous to provide a targeting ring to aid in the placement of the Kirschner wire under x-ray supervision.
The methods and apparatus of the present invention provide the foregoing and other advantages.
The present invention relates to a Kirschner wire for use in endoscopic surgery, as well as methods and apparatus for installing and removing the Kirschner wire. In particular, the present invention relates to a Kirschner wire having a holding device at a proximal end for ease of insertion and removal of the Kirschner wire. The Kirschner wire is sufficiently short so as not to protrude from the working channel of the endoscope. The insertion instrument has a receptacle which is adapted to engage with the holding device of the Kirschner wire. A targeting ring on the insertion instrument enables placement of the Kirschner wire under x-ray supervision. A removal device has a wire body with a receptacle located at a distal end thereof for engagement with the holding device of the Kirschner wire. The Kirschner wire may be adapted for use in marking a point of entry for a cannulated bone screw or as a point of orientation for an endoscopic procedure.
In an exemplary embodiment, a Kirschner wire for use in endoscopic procedures is provided. The Kirschner wire has a wire body with distal and proximal ends. A holding device is provided at the proximal end of the wire body for use in installing and removing the wire. The Kirschner wire may have a trocar point at the distal end of the wire body.
In a preferred embodiment, the holding device comprises external threads on the proximal end of the wire body. Those skilled in the art will appreciate that the holding device may also comprise internal threads on a cannulated portion of the proximal end of the wire body. The threads may be fine-pitch threads. Alternatively, the holding device may comprise any other type of interlocking mechanism which can be mated to a corresponding mechanism on an insertion instrument or a removal device for use in installing and removing the Kirschner wire during a surgical procedure.
Regardless of the nature of the holding device, it is preferable if the diameter of the holding device is equal to or less than a diameter of the wire body. This enables the wire to be removed through a cannulated instrument, such as a cannulated screwdriver.
It is preferable if the Kirschner wire is sufficiently short so as not to protrude from the working channel of an endoscope. In an exemplary embodiment of the invention, the length of the wire body is approximately 80 mm and the diameter of the wire body is approximately 2 mm.
The Kirschner wire may be adapted for use with an endoscope to provide a defined entry point for a bone screw or a defined point of orientation for an endoscopic procedure.
The Kirschner wire may be placed endoscopically using an insertion instrument. The insertion instrument has a hollow tube body for guiding the Kirschner wire. A plunger within the hollow tube body has a receptacle at a distal end thereof for engagement with the holding device of the Kirschner wire. A piston is connected to the plunger for use in driving the Kirschner wire to a desired depth (e.g., into a bone segment). A housing at the proximal end of the tube body is provided for guiding the piston. A metal targeting ring is provided on the housing for guiding the placement of the Kirschner wire using x-ray supervision.
The holding device may comprise external threads on the proximal end of the Kirschner wire. In such an embodiment, the receptacle will comprise corresponding internal threads on the distal end of the plunger. As discussed above, the holding device and the corresponding receptacle on the insertion instrument (and the removal device as discussed below) may take a variety of forms.
Where the holding device comprises threads, the Kirschner wire can be disengaged from the plunger by turning the plunger.
Preferably, the diameter of the holding device is equal to or less than a diameter of the Kirschner wire.
A stop may be provided at the distal end of the tube body for limiting a driving depth of the Kirschner wire.
In a further embodiment, a handle may be provided on the insertion instrument which extends transversely from the housing. The handle may be detachable.
The Kirschner wire may be removed endoscopically using removal device. The removal device has a wire body with a receptacle located at a distal end thereof for engagement with the holding device of the Kirschner wire. A handle is provided at a proximal end of the wire body for use in pulling the wire body after engagement with the Kirschner wire.
In one embodiment, the holding device comprises external threads on the proximal end of the Kirschner wire. In such an embodiment, the receptacle of the removal device comprises corresponding internal threads on the distal end of the wire body of the removal device. The diameter of the holding device is preferably equal to or less than the diameter of the Kirschner wire. In addition, the wire body of the removal device preferably has a diameter equal to a diameter of the Kirschner wire.
The removal device may be adapted for insertion into a cannulated insertion device. Alternatively, the removal device may be adapted for insertion into a cannulated screwdriver.
The invention also provides for a system for endoscopic insertion and removal of a Kirschner wire. The system consists of the insertion instrument, the removal device, and the Kirschner wire. The Kirschner wire has a first wire body with distal and proximal ends. A holding device is provided at the proximal end of the first wire body for use in installing and removing the Kirschner wire.
The insertion instrument for inserting the Kirschner wire has a hollow tube body for guiding the Kirschner wire. A plunger located within the hollow tube body has a first receptacle at a distal end thereof for engagement with the holding device of the Kirschner wire. A piston connected to the plunger is provided for use in driving the wire to a desired depth. A housing is provided at the proximal end of the tube body for guiding the piston. A metal targeting ring is provided on the housing for guiding the placement of the Kirschner wire using x-ray supervision.
A removal device for removing the Kirschner wire has a second wire body with a second receptacle located at a distal end thereof for engagement with the holding device of the Kirschner wire. A handle located at a proximal end of the wire body is provided for use in pulling the wire body after engagement with the Kirschner wire. In this manner, the Kirschner wire can be detached from the bone segment and removed from the endoscope.
The Kirschner wire further comprises a trocar point at the distal end of the first wire body.
The holding device may comprise external threads on the proximal end of the first wire body. The first receptacle may comprise corresponding internal threads on the distal end of the plunger. The second receptacle may also comprise corresponding internal threads on the distal end of the second wire body. The external and internal threads may be fine-pitch threads. In such an embodiment, the Kirschner wire car be disengaged from the plunger of the insertion instrument by turning the plunger.
The diameter of the holding device is equal to or less than a diameter of the first wire body of the Kirschner wire. The length of the Kirschner wire body is approximately 80 mm and the diameter of the Kirschner wire body is approximately 2 mm.
The Kirschner wire provides at least one of a defined entry point for a bone screw and a defined point of orientation for an endoscopic procedure.
A stop at the distal end of the tube body of the insertion instrument may be provided for limiting a driving depth of the wire. In addition, a handle may be provided on the insertion instrument extending transversely from the housing. The handle may be detachable.
In a preferred embodiment, the second wire body of the removal device has a diameter equal to a diameter of the first wire body of the Kirschner wire.
The removal device is adapted for insertion into a cannulated insertion device. Alternatively, the removal device is adapted for insertion into a cannulated screwdriver.
A method for inserting a Kirschner wire is also provided. A Kirschner wire having a holding device at a proximal end thereof is inserted into a distal cannulated end of a hollow tube body of an insertion instrument. The holding device of said Kirschner wire is engaged with a receptacle of a plunger within said hollow tube body. The Kirschner wire is positioned during a surgical procedure using an x-ray device. The Kirschner wire is driven into a bone segment by striking a piston connected to the plunger. Once driven into the bone segment in the appropriate position, the Kirschner wire may be disengaged from the plunger.
The holding device may comprise external threads on the proximal end of the wire body. The receptacle may comprise corresponding internal threads on the distal end of the plunger. In such an embodiment, the step of engaging the holding device with the receptacle comprises threading the Kirschner wire into the distal end of the plunger. The step of disengaging the Kirschner wire from the plunger comprises unthreading the plunger from the Kirschner wire.
A metal targeting ring may be provided on a housing of the insertion instrument to aid in positioning of the Kirschner wire using the x-ray device.
A method for removal of a Kirschner wire from a bone segment is provided. A cannulated instrument is inserted over the Kirschner wire. A removal instrument is introduced into the cannulated instrument. A receptacle located at a distal end of the removal instrument is engaged with a holding device located at the proximal end of the Kirschner wire. A handle at a proximal end of said removal instrument is pulled to disengage said Kirschner wire from the bone segment.
The cannulated instrument may comprise an insertion instrument. Alternatively, the cannulated instrument may be a cannulated screwdriver.